The siren series In-ear monitors are named after famous rock songs about women.
Jerry Harvey Audio produced a special version of the Roxanne tuned for the Astell&Kern in 2014. The collaboration was so successful that the two companies will now release two more models.
The first new model is the Layla. This all new flagship model is nothing short of stunning visually as well as sonically....

“These headphones have a nice open soundstage for an earbud headphone and are relatively comfortable to wear. The sound does seem to "settle" and refine somewhat after some time of burning in. They sound quite natural and relaxed especially at lower volumes but turn up the volume and these bad boys come alive. I find the slightly flat sound at lower volume levels does pay off at higher listening...” --pete4sound